Loading device for drafting arrangements



Feb. 14, 1961 E. EGGENSCHWYLER 2,971,326

LOADING DEVICE FOR DRAFTING ARRANGEMENTS Filed Jan. 30, 1957 7 3Sheets-Sheet 1 INVENTOR. E0 UA ED E'cGE/vscH WXL 518i ATTOIFNEK Feb. 14,1961 E. EGGENSCHWYLER 2,

LOADING DEVICE FOR DRAFTING ARRANGEMENTS Filed Jan. 30, 1957 3Sheets-Sheet 2 IN V EN TOR.

EDUA RD EGGENSCHWYLER.

ATTORNEY.

Feb. 14, 1961 E. EGGENSCHWYLER 2,971,226

LOADING DEVICE FOR DRAFTING ARRANGEMENTS INVENTOR. E0 UA PD EGGENSCHWrLE/W United States atent O LOADING DEVICE FOR DRAFTING ARRANGEMENTSEduardEg'genschwyler, Winterthur, Switzerland, assignor to Job. JacobRieter & Co. Ltd;, Winterthur, Switzerland, a corporation of SwitzerlandFiledJan. 30, 1957,Ser. No. 637,182

Claims priority, application Switzerland Feb. 15, 1956 Claims; (Cl.19-435) The presentinvention relates to a loading system for draftingarrangements in spinning machines and more particularly to a loadingsystem for the top rolls of draftin'g arrangements whereby the load isproduced by means of a pressure fluid.

Top rolls of drafting arrangements which rolls are indirectly loaded bya pressure fluid have been proposed; In the conventional arrangementsthe load is transmitted by levers to the top rolls. The conventionalsystems are all. unsatisfactory because? the adjustability of the rangeWithin which the load conditions change is very limited.

Directly pneumatically loaded top rolls have been proposed which arelocated within the carrier of the top rolls, the carrier beingconstructed as a guide arm. Because of the small available space, thisarrangement is suitable only for medium sized loads and cannot be usedfor great loading forces.

The shortcomings and limitations of the aforementioned conventionalsystems are avoided with the arrangement according to the invention inwhich the transmission of the load from an internally pressurized oblongelastic hollow body whose longitudinal axis is normal to the'rotationaxes of the top rolls is effected througha plurality of shoes resting onthe hollow body and being tiltable relatively to each other in adirection which is parallel to the longitudinal axis of the body. Groupsof the shoes are individually engaged by pressure transmitting elementswhich are individually operatively connected with the top rolls in sucha manner that the sum of the forces transmitted from the pressure shoesof a group to the respective transmitting element is the same at anyposition of the top rolls and of the transmitting element relatively tothe longitudinal extension of the elastic body.

The novel features which are considered characteristic of the inventionare set forth with particularity in the appended claims. The inventionitself, however, and additional objects and advantages thereof will bestbe understood from the following description of embodiments I thereofwhen read in connection with the accompanying drawing in which:

Fig. l is a diagrammatic elevation of a loading system according to theinvention for a drafting arrangement;

Fig. 2 is a cross sectional view of the lower part of the loading systemshown in Fig. 1;

Fig. 3 is a vertical longitudinal sectional view of the lower part ofthe system shown in Fig. 1;

Fig. 4 is a longitudinal vertical view of the lower part of a modifiedloading arrangement.

Like parts are designated by like numerals in several figures of thedrawing.

Referring more particularly to the drawing, numerals 1 to 6 designatefluted rollers which form together with top rolls 7 to 10 a conventionaldrafting arrangement. In order to adjust the spacing of the nips formedby the fluted rollers and the top rollers according to the staple of thematerials to be worked, it is necessary that the position of the toprolls can be changed longitudinally of the 2,971,226 Patented Feb. 14,1961 ICC drawing frame. Each top roll is loaded at both ends by means ofa tension rod 11 forming part of a pressure transmitting element. Thelatter includes a hook 12 which is adjustably connected with the lowerend of the rod 11 by means of a screw connection, the hook including aridge portion 13 (Fig. 2) which is connected with the screw connectionby an arcuate portion 14 whose upper end is provided with an aperturefor receiving the threaded lower end 15 of the rod 11. The load forcesare produced in an internally pressurized hose 17 which is received inan inverted U-shaped channel 16. -A plurality of" pressure shoes 18transmit the pressure from the hose 17 to the ridgeportion113 of thehook12. The ends of the channel 16 are rigidly connected with a portion of:the; frame 20 of the spinning machine which is provided for this purposewith suitable recesses 19'. A portion of the frame 20 is'sho'wn in Fig.2.

The channel 16 has two' leg portions, 21 and 22 which are provided withinternally projecting flanges 24 and 23, respectively, leaving: alongitudinal slot 25 below the longitudin'al axis of the tube 17. Theaforesaid pressure shoes 1:8 areplaced between the. hose 17 and theflanges 23 and 24, each shoe having two downwardly projectingprotuberances zfi and 27 forming a V-shaped recess 28. The bottoms ofthe recesses are substantially parallel tothe longitudinal axis of thehose 17 and are adapted to receive the ridge 13- of the hook 12. Thepressure shoes 18 have shoulders 29 which rest on the flanges 23 and 24,preventing falling of the pressure shoes out of the channel 16 when theshoes are not supported by or are not pressed against the ridge portion13 of the hook 12.

The pressure shoes 18 are provided with head portions 30 having twooppositely positioned lateral substantially cylindrical surfaces 31 and32 which abut against corresponding surfaces on the neighboring pressureshoes. This prevents jamming, if the shoes move relatively to each othertowards and from the axis of the hose 17.

As is evident from Fig. 3, the sum of the forces transmitted from thepressure shoes 18 to the hook 12 remains the same and is independent ofa displacement of the hook 12 along the longitudinal axes of the hose 17and of the channel 16. If the force transmitted from the hose 17 to ashoe 18 has the value P, a force P-l-P-acts on the hook 12 in theposition shown in Fig. 3 which force is exerted by the shoes which arecompletely in engagement with the ridge portion 13; in addition there isa force 2 P/2 derived from the shoes of which only a part rests on theridge portion 13.

A reaction P/2 is transmitted from the shoulders. of the shoes ofwhichonly a portion engages the ridge portion 13 to the flanges 23 and24. The total of the loading forces amounts to 3?. There is anotherpossible position of the hook 12, if the latter is provided with a ridgeportion substantially as long as the total length of the space taken bythree abutting pressure shoes. In this position three pressure shoesrest entirely on the ridge portion so that the force exerted on the book12 is again 3P. In this case there are no additional P/2 reactionsbecause the pressure shoes which are on the left and on the right of thethree shoes engaged by the ridge portion 13 do not take any hold on theridge portion. It is, therefore, clear that the force transmitted fromthe hose 17 through the pressure shoes 18 to the hook 12 is always thesame and independent of the position of the hook 12 longitudinally ofthe hose 17. Of course, in actual practice this load may change up to20% and such minor changes are included, if the term constant load isused in this specification and in the appended claims. This variation ofthe load is caused by friction effects which cannot be completelyeliminated. The more flexible the hose 17 the more the load is likely tobe the same in 3 different positions of the book 12 relatively to thehose 17.

The length of the ridge portion is preferably so that never more thanthree pressure shoes transmit their entire force to the hook 12. Aparticularly suitable length of the ridge portion has been found toamount to the space taken up by two and one half adjacent pressureshoes. If the structure of the drafting arrangement permits this, thenumber of pressure shoes acting on the ridge portion of the hook 12 maybe increased to three and one half or to four and one half, i.e., to nminus one half, n designating the number of the transmitted pressureshoe loads.

When using a design of the pressure shoes, as shown in Fig. 4, thislimitation need not be made to the same extent. The heads 33 of thepressure shoes 32, 32 32 32 32, 32 are not provided with lateralcylindrical surfaces, but are provided with articulations which preventa mutual vertical sliding of adjacent heads. As seen in Fig. 4, theheads 33 are provided on one side with an edge portion 34 and on theother side with a recess 35 which is adapted to receive the edge portion34 of the head of the adjacent pressure shoe. In the modification shownin Fig. 4, the forces transmitted from the pressure shoes to the book 12remain the same and are independent from the position of the hook 12along the longitudinal extension of the hose 17. The ridge portion 13 ofthe hook may decline slightly from the longitudinal axis of the hose 17towards the ends of the ridge portion because the position of thepressure shoes 32 is not defined by the abutment of the shoulders of thepressure shoes against the flanges of the channel and by the engagementof the V-shaped recess of the pressure shoe with the ridge portion, asis the case in the modification shown in Fig. 3. The pressure shoe 32which is in inclined position, is held on its left side by the edge 34received in the recess 35 of the adjacent pressure shoe 32 which absorbsthe reaction P/2. The right side of the pressure shoe 32 sits on theridge portion 13. The modification shown in Fig. 4 has the advantagethat there are no edges which cut into the hose 17 and the hose, restsmore smoothly on the heads of the pressure shoes. The result isincreased accuracy of load distribution. Instead of providing edges 34and complementary recesses 35, the articulations may be made byproviding spherical protuberances and corresponding cavities.

The loading arrangement according to the invention operates accuratelyonly if the tension rods and respective hooks are always at a rightangle to the longitudinal axes of the channel 16 and of the tube 17.

This requirement is complied with in horizontal drafting arrangements,as in drafting frames, and the like,

and there are no special provisions needed for applying the invention.The described and illustrated loading arrangement is particularlysuitable for drafting arrangements of this kind.

I claim:

1. A loading device for the top rollers of a drafting arrangementincluding an internally pressurized elastic hollow body, a plurality ofpressure shoes resting against the outside of said body, and a pressuretransmitting element interposed between a plurality of said shoes andone of the top rollers and having a first portion engaging a pluralityof said shoes, said pressure transmitting element having a secondportion engaging a top roller, said elastic hollow body being inthe formof a hose and said pressure shoes being arranged in a row substantiallyparallel to the longitudinal axis of the hose, said pressure shoeshaving head portions of a greater peripheral extension than the rest ofsaid shoes, said head portions engaging said hollow body and laterallyengaging the head portions of neighboring shoes, said head portionsbeing so shaped as to afford relative tilting of adjacent pressure shoesand simultaneous retention of the positions of the pressure shoesrelatively to the longitudinal axis of said hose.

2. A loading device according to claim 1 in which the length of saidfirst portion amounts to n'minus one half of the dimensions of saidpressure shoes measured between the points of engagement of saidpressure shoes, n designating the number of loads produced by theindividual pressure shoes which number is desired to be transmitted bysaid pressure transmitting device.

3. A loading device according to claim 1 in which said head portions areprovided with articulations interconnecting the head portions ofneighboring shoes.

4. A loading device according to claim 3 in which said first portion ofsaid pressure transmitting device declines from the center line of saidhose at either end of said first portion.

5. A loading device for the top rollers of a drafting arrangementincluding-an oblong channel element whose longitudinal axis extendssubstantially normal to the rotation axis of the top rollers, aninternally pressurized oblong elastic body received in said channelelement in parallel relation thereto, a plurality of pressure shoesplaced in said channel element adjacent to one another to form acontinuous line parallel to the longitudinal axis of said body, saidchannel element having a longitudinal opening, said shoes restingagainst the outside of said body and facing the opening of the channelelement, said shoes being individually tiltable on axes which are normalto the longitudinal axis of said body, and a pressure transmittingelement interposed between a plurality of said shoes and one of the toprollers and having a first portion engaging a plurality of said shoes,said pressure transmitting element having a second portion engaging atop roller, said pressure shoes including portions located inside andcooperating with the inside of said channel element for retaining saidshoes inside said channel element, all said pressure shoes having thesame size and configuration and being tiltable relatively to each otherfor transmitting a pressure equal to the sum of the pressures exerted bythe individual pressure shoes en-.

gaged by said first portion of said pressure transmitting element to thelatter independently of which of the pressure shoes are engaged by saidfirst portion.

References Cited in the file of this patent UNITED STATES PATENTS GreatBritain June 24, 1953

